My kiddos are loving the place value activities from Regan Tunstall’s Guided Math Place Value Unit.  I have been using her activities in my math workshop and the kids LOVE them.  I use Math Expressions as my primary resource because it is our district adopted curriculum.  Math Expressions doesn’t lend itself to small group intervention as well as Regan’s units do.  It takes a bit of prep work to match the unit activities up but it is well worth it.  For this activity we are adding 10 and taking away 10.  I thought it would be way more fun to make our number lines on the playground.  My daughter has an over abundance of sidewalk chalk so it was easy for every student to have their own chalk.  We made number lines that started at 10 and went up to 120 by 10’s.  I started by calling out a number and they would jump to it on their own personal number line.  Then I would say add 20.  They would jump ahead 2 and we would all shout out what number we were on.  When the kids were really good at adding 10’s I started having them subtract 10’s.  Finally I started mixing addition and subtraction together.  They did a fantastic job.